In the art of vending and dispensing beverages, it is common practice to provide beverage dispensing machines with beverage supply tanks in which supplies of beverage are maintained and which are provided with automatically or manually operated dispensing valves to dispense the beverages into drinking glasses or containers, a serving at a time. The beverages received and dispensed by such machines are most commonly reconstituted beverages established by the measuring and mixing together of predetermined portions of water and beverage concentrates.
While throughout the art both dry or granulated and liquid beverage concentrates are used, liquid concentrates are most commonly used and are those concentrates which the liquid metering and mixing unit of the present invention is intended to work upon.
In the case of liquid beverage concentrates, there are concentrates which are very thin, of low viscosity and which are therefore such that they are easily moved or caused to flow and there are concentrates which are in the form of thick, viscuous syrups which are not easily moved or caused to flow. For example, those non-sweetened beverage concentrates, such as coffee or tea concentrates are characteristically very fluid and free-flowing while those sweetened and sugar ladened fruit flavored beverage concentrates, such as fruit punch, are characteristically very viscuous and slow flowing. The viscosity and flow characteristics of different brands and flavors of beverage concentrates are subject to notable differences and the work energy required to cause them to flow, as for the purpose of delivering or dispensing measured volumes thereof, differs widely.
In practice, the proportional volumes of concentrates and water required to reconstitute beverages vary from 5 to 20 parts of water to each part of concentrate, depending upon the strength of concentrate and the kind or type of beverage produced thereby.
Throughout the years, the prior art has provided beverage dispensing machines with various apparatus and/or means to automatically mix together and deliver into the machines predetermined volumes of water and liquid beverage concentrates whereby the inconvenience, expenditure of time and potential human error expended and experienced in the practice of manually measuring and mixing the ingredients is avoided.
To date, the most effective and practical of those automatic mixing means provided by the prior art have utilized and have been characterized by aspirator devices or units which are suitably connected with pressurized water supplies (such as municipal water service systems) and which are connected with supplies of liquid beverage concentrate in or positioned near the dispensing machines. Such automatic mixing means commonly include an on and off valve to control the flow of water into and through the aspirator devices and the devices are such that the volumes of water caused to flow through and which are delivered by them draw and carry proportional volumes of the concentrates. In those instances where those thin, unsweetened beverage concentrates are being worked upon, effective mixing of the water and beverage concentrates occurs substantially instantly and automtically when the two liquids are brought together. On the other hand, in those instances where thick syrupy sweetened beverage concentrates are worked upon, the mere bringing together of the two liquids within the aspirators does not result in effective mixing of the liquids and separate and/or special means, downstream of the aspirators, must be provided to assure complete and proper mixing of the liquids.
The aspirators adopted and used by the prior art to deliver water and beverage concentrates into beverage dispensing machines have been of very standard "text-book" design and construction and have proven to be quite ineffective. Typically, those aspirators have consisted of straight cylindrical small diameter water nozzle tubes or passages with receiving ends connected with related water supplies and other discharge ends at or within the inlet or closed ends of short cylindrical large diameter mixing tubes or chambers; and liquid supply tubes or ducts communicating with supplies of liquid concentrate and opening at one side of the closed end portions of the mixing tubes or chambers. The other or discharge ends of the mixing tubes or chambers simply open directly into a space defined by some related structure to effect free discharge of the liquids from the mixing tubes or chambers. Concentric relationship of the nozzle tubes or passages and the mixing tubes or passages has not been deviated from and the limited use of the motive force of the water flowing through the aspirators by premature and ineffective discharge of the liquids from the discharge or open ends of the short mixing tubes or chambers has not been deviated from.
With few exceptions, those aspirators which have been adopted and used by the prior art (within those operating parameters inherent in the environments in which they are used) are capable of drawing about 8", plus or minus 4" of mercury. Such limited effectiveness of efficiency has resulted in a situation wherein certain of the heavier and more viscuous syrup concentrates cannot be effectively moved and worked upon by the automatic aspirator type mixing means provided by the prior art and has resulted in a situation where the design and arrangement of all of the components and/or parts of and for such water and beverage concentrate mixing means are controlled and limited by the notable inefficiency and ineffectiveness of the aspirators.
Typically, the automatic aspirator type mixing means for beverage dispensing machines which the prior art has provided have been designed and fabricated in a step-by-step manner with each phase and/or function handled and performed by some separate means or structure. As a result, such concentrate mixing means have characteristically consisted of elongate series of components and parts which are inherently slow to operate. That is, they are such that they must be operated substantial periods of time before they are completely primed and fully operational. The foregoing has materially limited the practical use of automatic water and beverage concentrate aspirator type mixing means.
It has been noted that in the art here concerned with, the prior art has not come forth with one or more standard commercially available aspirator devices or units which might be produced and offered for sale in the same manner that standard commercially available valves and pressure regulators are produced and made available. Instead, in each instance or case where an aspirator is required, a special aspirator unit or device is designed and produced, which will effectively handle a particular type or class of concentrate and will effectively deliver a desired proportional mix of concentrate and water when said water is delivered to the structure within a limited range of pressure. The foregoing is understood and believed to be the result of the fact that no single aspirator or device has been designed, produced and offered for sale which is sufficiently effective and efficient throughout a wide range of operating parameters for universal application in this art and the art has therefore been left to improvise and/or design special aspirators whenever the provision and use of an aspirator is required.